it is a good idea to get backlinks to as many different pages within a single domain as possible. Sub.Domains are an excellent way to grow a domain.
We can get hundreds of one way backlinks to each of your sub.domains, using niche keywords, to help boost your overall domain authority. visit us at
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we are running a 2 for 1 special.
Hope that answers your question.
Have a nice day,
~Ray